May 30, 2020
Since January 1st, 1,131 national polls asked “Do you approve or disapprove of the way Donald Trump is handling his job as president?” The average percent of “Disapprove” for these 1131 surveys is 53.3%.
That virtually every national poll contains this question suggests that it has some significant importance that should effect voters’ political vote choice. But almost all studies suggest otherwise, that is until right before the election.
But I don’t find any academic studies on the effect that a President’s job approval has on their polling percent of the vote. You would expect a high degree of probability between the two variable.
To test this hypothesis, I obtained all 1,131 surveys conducted from January through May 26th, 2020 that contained both the standard job approval rating and the trial ballot question between Biden and Trump in the same survey.
In this time period, Trump had a net positive (approve less disapprove) rating in only four surveys, as shown in the chart below where the net positives are above the horizontal line.
His job rating has been underwater for most of his time in the White House. If Trump’s Job Approval rating were predictive at this point, I would recommend he put a reservation on a moving van for the fall. But as I have pointed out before, this variable has a short shelf-life and only predictive when measure close to the election.
In the Biden/Trump elections question, Trump has a 41.9% average against Biden’s 49.7%, an average lead of 7.8% for all 1,131 surveys.
His Biden/Trump polling is out performing his job approval rating by 1.7%. The chart below shows how his percent of the Biden/Trump poll changes as his disapproval rating changes.
This graph depicts what happens to Trump’s percent of the Biden match-up as more voters say they disapprove. That, of course, means that the people who are least likely to vote for Trump are those who disapprove his job performance.
This shouldn’t be a surprise since people who do not like someone will never vote for him or her, and people who do like him may or may not vote for him. What is surprising is that the “approval” rating is does not effect his polling percent.
I can now calculate the average reduction of Trump’s disapproval rating based on the regression model’s standardized coefficient estimate’s reduction of his percent of the two-party poll percent against Biden. The model coefficients are shown in the table below.
|Model||Unstandardized Coefficients||Standardized Coefficients||t|
We can calculate Trump’poll percent of the vote against Biden’s with a simple equation: Y = -.547 (x) + Constant (68.95), where x is Trump’s disapproval rating and Y is the Trump’s percent of the vote against Biden. Notice that the significant (Sig.) level for “Approval” is .684, and non-significant at the <.05 standard.
Trump’s average disapproval rating in these surveys is 53%. So our equation is Y = -.547 (53) + 68.95 or Trump percent of vote =40%, 1% less than the actual average of all polls.
What is this analysis suggests is that Trump’s job disapproval rating is far more important than his approval rating in determining his percent of the vote. In fact, the approval rating in this analysis is not significant, meaning it has no impact on his percent of the vote.
Will this apply to the actual election in November? The honest answer is I don’t know. Normally, models that predict election outcomes use past election data (along with other exogenous variables, such the economy).
But the President’s “approval”rating has been shown to predict his re-election when polled near the election. No president since modern polling has won re-election with an approval less than 50% on election day.
Because of the inverse relationship, when the approval number is 50%, the disapproval rating is likely around 46% (excluding the “don’t knows”). As we get near the election, I will revisit this equation again to see if it does predict the winner.
In the mean time, when you see a 2020 poll, check out the disapproval rating. If it is more than 37%, he’s losing…